What is a relational database?

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A relational database is a collection of data logically organized so the information can be easily edited, added to, deleted, and most importantly, accessed. Relational databases, which store data in structured tables, are one of the most popular and easy-to-use types of databases.

You might be familiar with traditional spreadsheets, which also store data in tables. However, unlike traditional spreadsheets, which were originally developed to function like accounting worksheets for financial calculations, relational databases were specifically designed to store information reliably and scalably. Because of this, relational databases offer vast flexibility in terms of what you can do with information.

While databases used to be exclusively the domain of developers, and out of reach for the average person, now, they can be mastered by just about anyone given the right tools. Once you understand the components of relational databases, you can begin to envision how to construct and use them for your particular needs—whether you’re hoping to manage a project for a large team or simply build a record-keeping system that will be scalable and help eliminate mistakes.

Let’s start at the top.

A database is the container for all your data. (In Airtable, we simply call it a base.)

Look inside a database, and the first thing you’ll find is at least one table.

What is a table?

Tables are the main building blocks of relational databases. Each table is a data set composed of records and fields, and represents a single subject.

Each of the tables within a database contains a logically organized set of information.

For instance, if you’re an event planner, you might have a table for events, a table for venues, a table for vendors, and a table for clients. Each of these tables contains all of the relevant data for that specific subject: for example, the event table might contain dates and times for each event. Inside a table, the data is arranged into records and fields.

Nerd alert: the technical term for a table in a relational database is “relation.” In 1970, Dr. Edgar F. Codd first proposed the relational database model in a paper titled “A Relational Model of Data for Large Shared Databanks.” His model was heavily based on mathematical set theory, and the name “relation” for a table is based on terminology from set theory. A common misconception is that the term “relation” comes from the fact that the tables in a relational database “relate” to each other.

What are records?

In a relational database, a table represents a single subject; a record is a unique instance of that kind of subject. For example, in an event planner’s database, each record in the events table represents a different event (“The City Museum 15th Annual Fundraising Gala,” “Equilux Holiday Party,” etc.); each record in the vendors table represents a different vendor (“Objectively Edible Catering,” “By the Bouq Flowers,” etc.); and so on.

This sample database has four tables: Events, Venues, Vendors, and Clients. Each table has a couple of example records within it. Try clicking through the different tabs to explore the tables.

Nerd alert: Any mathematicians in the house? You might know records by another name: tuples. A tuple is a finite ordered list of elements.

If you’re familiar with traditional spreadsheets and their grid format, you might

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